Startup rolls complementary litho

SAN JOSE, Calif. – At the SPIE Advanced Lithography conference here, maskless startup Multibeam Corp. will outline more details about its ongoing efforts to commercialize its so-called Complementary E-Beam Lithography (CEBL) technology in the market.  

Multibeam (Santa Clara, Calif.) will describe the latest developments of its CEBL tool, a multi-column, maskless lithography system designed for patterning the most critical layers in a design–contact holes, vias and line cutting–at the 16-nm node and beyond. Throughput is said to be five wafers an hour–more than twice the speed of today’s single-beam e-beam tools.   

David Lam, venture capitalist and chairman of Multibeam, said CEBL will not replace today’s optical lithography. But rather CEBL ''complements’’ or works in tandem with today’s 193-nm immersion tools, Lam told EE Times. Multibeam is looking for partnerships to enable CEBL, he added. (Lam is also noted for being the founder of Lam Research Corp. He is no longer associated with Lam Research.)       

At SPIE, Multibeam, along with Tela Innovations (Los Gatos, Calif.), will also present a paper, entitled ''E-beam Litho to Complement Optical Lithography for 1D GDR.’’ 1-D GDR, or one-dimensional gridded design rule, is based on Tela’s 1-D layout optimization technology. The combination of CEBL and 1-D gridded design rule technology could provide a powerful one-two punch to enable next-generation IC designs at 22-nm and beyond, he said.   

Today’s optical lithography could hit the wall, prompting the need for another next-generation lithography (NGL) solution.  Direct-write or maskless, EUV and nanoimprint are among the next possible waves in lithography.

For years, the industry has used direct-write e-beam technology to pattern lines directly on a wafer. Today’s direct-write tools make use of a single-beam technology. E-beams are also used in mainstream photomask production.

Direct-write promises to give chip makers some relief from the soaring costs of photomasks. Direct-write prints tiny features on a wafer, but it is slow in terms of throughput, thereby relegating the technology to niche applications like compound semiconductors. For the most part, direct-write is too slow and expensive for mainstream IC production.

In the last decade, a number of companies began working on next-generation e-beam technology, dubbed maskless lithography or ML2. IMS, KLA-Tencor, Mapper, Multibeam and others are separately working on tools that utilize multiple beams in a single machine. In theory, ML2 is supposed to overcome the throughput issues associated with single-beam direct-write.

Formed in 2001, Multibeam emerged from stealth mode in 2005. At about that time, the company obtained approximately $2 million in funding from the National Institute of Standards and Technology (NIST). The startup also disclosed that it was developing a maskless, 50-KeV tool that utilized an array of 10 electron beams.

At the time, Multibeam was among several vendors racing to develop a tool in NGL. In NGL, there are several technologies aimed to replace today’s optical lithography, such as extreme ultraviolet (EUV), maskless and nanoimprint.

Then, in 2009, Multibeam entered into a joint development program with Japan’s Tokyo Electron Ltd. (TEL) for an undisclosed project. But in more recent times, Multibeam has narrowed its focus.

Instead of replacing optical lithography, Multibeam’s new strategy is to work in tandem with 193-nm immersion-or perhaps another technology-in mainstream fabs. ''We are not an NGL,’’ Lam said. ‘’We will not replace optical in high-volume manufacturing anytime soon.’&